Machine for dissolving xanthates



Feb. 24, 1931. RM ET AL 1,794,214

MACHINE FOR DISSOLVING XANTHATES Filed Jan. 20, 1930 L1] 5 Y .Z .5 INVENTORS RICHARD JHURM BYZLUGEM SCMVIERER memes Feb. 2e, rear 7 E3942 la UNITED STATES PATENT OFFICE RICHARD THURM AND EUGENE SCHMIERER, F SAGINAW, MICHIGAN, ASSIGNORS TO BAKER PERKINS COMPANY, INC., 01 SAGINAW, MICHIGAN, A CORPORATION 01- NEW YORK MACHINE FOR DISSOLVING XANTHATES Applieation fil ed January 20, 1930. Serial No. 421,943.

5 ment and mode of operation of the central vertical drum andits cutting and circulating mechanism,- whereby the time required for mixing and dissolving each batch of material is notably'reduced and the hourly output is increased, constitutes the subject matter of the present improvement.

The object of the invention is to secure maximum dissolving effect during each single circuit of the material through the drum, as distinguished from the action of prior de vices that depend for their output capacity upon traversing the circuitthrough the machine many times, consequently requiring more prolonged treatment.

The improvement also includes a novel arrangement of grids and propellers for shearing and screening the material smaller and smaller as it passes downwardly through the drum.

The stated objects are attained by a novel arrangement of cutting grids within the central drum. They are-spaced apart axially of the drum, and neighboring grids define between them a plurality of chambers or zones that progressively decrease in size toward the bottom. The material under treatment is agitated in each chamber in succession during its downward travel and immediately after each cutting.

In each downward passage through the drum the material is cut by each cutting unit (propeller and grid), in turn. Each out is finer than the preceding one.

During the time the material is in each of the chambers it is swirled and stirred and is subjected to a great amount of laving and dissolving action upon its freshly cut surfaces. The material passes through the next group of cutting elements, consisting also of av grid and a revolving propeller knife, where like action is repeated, followed by agitation in the next chamber. I 1

With the foregoing and certain. ther objects in view, which will appear later in the. specification, our invention-comprises the de-.

vices described and claimed andthe equiva-' lents thereof.

In the drawings Fig. 1 is a fragmentary part sectional view of the lower part of a mixing bowl with our improvement applied thereto.

Fig. 2 is a sectional view of the upper statlonary cutting grid, the section taken on line 22 of Fig. 1.

Fig. 3 is a plan view of the lower cutting grid, taken on line 3-3 of Fig. 1, the cage or cylindrical grille being shown in place.

P Fig. 4 is a fragmentary view of the cage, the relative position of the bottom impeller blade being indicated by dotted lines.

Fig. 5 is a top plan view, partly broken away, showing thebottom paddle wheel.

Fig. 6 is a fragmentary detail in perspective showing the shearing relation of the sharpened top edge of the paddle blade to the shacrl'p-edged barof the coacting stationary grl 4 a The mixer bowl 1, preferably jacketed, has an upright open-ended drum 2 mounted therein, the lower part of the drum consisting of a screen or cylindrical grille 3. A powerdriven shaft 4 extends axially through the drum.v Fixed to the shaft, adjacent the bottom of the bowl and within the cylindrical grille 3 is a paddle wheel with blades 5 that lie in planes extending radially outward from the shaft4 and are tilted slightly away from the vertical.

The paddle blade margin which is adjacent the cylindrical cage 3 is preferably sharpened to provide a cutting edge 6 that cooperates with the interiorly sharpened bars of the cage to shear the material as it passes outwardly through the cage. Likewise, the upper horizontal'edge 7 of each blade 5 is sharpened.

' The middle area 8 ofeach blade 5 is cut away to reduce the impelling effect of the paddlewheel and toincrease the eddying effect within the cage 3.

Immediately above the paddle wheel is a grid 9' that extends horizontally across the drum. ,It consists of a peripheral rim 10, -Fig. 3,which is secured to the drum 2, a hub llwithin which the shaft freely-revolves,

' and radial bars 12 connecting the rim and hub. One or more circular rings 13, 14 located between the hub 11 and the rim 10 con-.

nects the several spokes, as shown in Fig. 3, to reinforce their resistance to-the' crosswise stresses that are set up by the revolving blades ofthe, propellers when they are cutting the material.

The edges 15 of the grid bars 9 that cooperate with the sharpened edges 7 of the paddle wheel blades 5 are also sharpened, and these two co-operating edges 7 and 15 shear the material in the manner indicated in Fig. 6.

The circular form of grid is advantageous for reinforcing the drum to resist strains developed by the cutting operation.

Immediately above the grid9 and fixed to the shaft 4 is a shearing element 16 of the typical propeller form commonly employed in this class of machines.

The lower edge 17 of the propeller blade is sharpened and 'thus is provided a plurality of shearing edges arranged in'the plane of the upper surface of the grid 9. The radial arms 12 of grid 9 are shar ened alon .their top edges to provide kni e edges. therefore has knife edges at both its top and bottom faces.

Vertically above the lowermost id and propeller blade just described an from them is another similarly arranged grid 18 and co-acting propeller 19 and above that, near the top of the drum, is still athird and'similar assembly 20 and 21. Thus the drum 2 is divided by the grids into an upper agitating and dissolving chamber and a similar intermediate chamber and abottom paddle wheel chamber.

The operation of the device is as follows:

-The flow induced bythe ropellers 21, 19, 16 takes place downward t1? 2 and through the respectivegrlds 20, 18, 9, and at the bottom of the drum the direction of flow is changed from downward to radially outward by ,the apertured paddle blades 5. Thence the flow is upwardly between the bowl 1 and the drum 2 and recirculation takes I place in known manner.

The new result attained by the mechanism above described-is that the material during its repeated circulation is forced by the top pro eller 21 through the top grid 20 and in so oing it is sheared by theco-operatiiig cutting edges of the pro eller and grid.

In the upper cham er thematerial is agitated and swirled, and because of the size of the cavity and the reduced" velocity of the material has opportunity for its freshly cut faces to become partly dissolved. After a short period in the upper chamber the ma terial is taken by the intermediate propeller 19, is again sheared and is projected through the intermediate grid18'into the intermediate chamber, where its freshly cut surfaces rid 9,

spaced rou h the drum are again subjected to dissolving and agitation while being given another short period of dwell or delayed travel. The bottom propeller then takes the material, shears it again and forces it through the bottom grid 9. The bottom grid is of 'finer mesh, as indicated in Fig. 3, than the upper grids 18 and 20 shown in Fig. 2.

The cylindrical grille or cage 3 at the bottom of drum 2 may be formed of heavy wire mesh, or perforated sheets, or it ma be built up of flat bars 22 arranged in the orm of a cylinder, as shown in Fig. 4, the fiat faces of the bars being disposed radially. The bars 22 are bound together by wires 22a welded hoo -wise around their outer edges, as shown in ig. 4." The ca e 3 serves in lieuof legs for supporting tie central drum. The drum and spaced propelling and shearin devices above described the material isurge with gradually increasingforce downwardly through progressively finer grids to the bottom of the drum, where it is caught by the apertured agitating paddle wheel blades and is driven forcefully outwardat high velocity against and through the fine'mesh cage3.

A single circuit of a given unit quantity of material through a machine arranged as above described results in reduction and dissolving to an extent that could otherwise be attained only by passage around the circuit again and again.

This-application is a continuation-m-part of our copending application Serial No. 151,488, filed November 29, 1926.

Having thus described our invention, what we claim desire to secure by Letters Patent is:

1. In combination with a mixer comprising a bowl containing an upright cylindrical drum havin a cylindrical cage at its lower end an a central rotatable shaft with a paddle impeller fixed to the shaft at the bottom of the bowl and within the cylindrical cage, a plurality of horizontal grids fixed in said drum one above the other and spaced apart to define between them a plurality of material-circulating and -dissolving chambers arranged in succession and of progressively smaller volumetrlc capaci- .19.) angularly' arranged blades on said shaft, 7

3. A structure as set forth in claim 1 wherein the addle blades are formed with apertures an are disposed in planes substantially upright but slightly inclined. with respect to the axis of the shaft.

In testimony whereof, we aflix our signatures.

RICHARD THURM. EUGENE SCHMIERER. 

